Machine for removing threaded dies from molded parts



June 10, 1952 v J. KREBS; JR 2,599,764

' I MACHINE FOR REMOVING THREADED DIES FROM MOLDED PARTS Filed Nov. 5,1949 I 2 smms-sxm'r 1 June 10, 1952 J, EBs, JR 2,599,764 v MACHINE FORREMOVING THREADED DIES FROM MOLDED PQRTS Filed Nov. :5, 1949 2SHEETS-SHEET 2 MIVDVTOR' J. KRL-BS JR.

Patented June 10, 1952 MACHINE FOR REMOVING THREADED DIES FROM MOLDEDPARTS John Krebs, Jr., Chicago, Ill., assignor to Western ElectricCompany, Incorporated, New York, N. Y., a corporation of New YorkApplication November 3, 1949, Serial No. 125,244

8 Claims.

This invention relates to a die extracting machine and more particularlyto a device for simultaneously unscrewing a pair of thread formingannular dies from a molded handle of a telephone handset in which theremovable dies are disposed on converging axes.

It is the object of the present invention to provide a mechanism forsimultaneously removing a pair of thread forming die members from amolded article.

In accordance with one embodiment of the invention two rotatable dieremoving heads mounted on shafts for rotation about converging axescorresponding to the converging axes of the pair of annular dies on themolded article are normally positioned to be engaged by the annular diesto establish a driving connection therewith. The shafts are connectedthrough gearing to a motor which is controlled by switch means springbiased to open position and actuated to closed position by an articlemoved into operative position in engagement with the heads. The dies,which move axially with the heads as the die are being unscrewed fromthe molded article, are interlocked with the heads and prevent theremoval of the article which holds the switch closed, and upon removalof the dies from the article the switch raises the article and isrestored to open position to stop the motor.

Other objects and features of the invention will be apparent byreference to the following detailed description thereof, and theaccompanying drawings, in which Fig. 1 is a vertical front elevationalview of the extracting machine with the article shown in spaced relationthereto,

Fig. 2 is a side elevational view of the machine,

Fig. 3 is a bottom view of one of the thread forming die rings,

Fig. 4 is a sectional view of the die ring taken on the line 4-4 of Fig.3; and

Fig. 5 is an enlarged detailed vertical sectional view of a portion ofthe extracting machine with a molded article in operative positionthereon.

In the molding of the handle ll] of a telephone handset, annular diemembers or rings it having internal threaded portions I 4 are insertedin the mold to form the external threaded end portions H; on the ends ofthe handle member ID. threaded portions 16 and the dies [2 are disposedat an angle relative to each other and in coaxial relationship withpredetermined converging axes. The annular dies l2 remain on the handleI0 when the handle is removed from the mold and have to be removedtherefrom. Each die I2 is The 2 provided with a plurality of notchesl8-l 8 which may be engaged with a rotatable tool to unscrew the ringsfrom the article.

The simultaneous removal of the thread rings l2 from the handle I0 isexpeditiously achieved in the present extracting machine which comprisesa pair of rotatable die removing heads 2020 adapted to be engaged by thedies l2 for removing the dies from the handle I0. Each of the headscomprise a cylindrical member or disc 22 having a fiat surface 24engageable with the end surface 25 of the dies and an upwardlyprojecting concentric conical portion 26 telescopingly engageable withthe annular dies for aligning the dies relative to the heads 28. A pairof diametrically opposed pins 28 secured to the upper portion of thedriving head is engageable in the slots it of a thread ring and forms adriving con-' nection therewith for imparting rotation to the threadring.

Each head is mounted for rotation with and for limited axial movement ona hollow shaft 30 through a spline 32. The hollow shafts 30 aresupported in bearings 34 mounted in a suitable framework or housing 36,and are disposed at a predetermined angle relative to each other .forrotation about converging axis which correspond to those of the threadedportions l6 and the dies E2 on the article [0. At the lower ends of thehollow shafts 30 are secured beveled gears 38 which mesh with a beveledgear 40 secured to a drive shaft 42 of a gear reducer unit 44 which inturn is secured to the housing 36. A sprocket and chain connection 46connects the gear reducer 44 to an electric driving motor 48 alsomounted on the housing 36. The housing. 36 may be supported in anysuitable manner. In the embodiment disclosed herein, the housing 36 issecured to a back plate 50 which is fastened by bolts 5! to one side ofa bench or table 52, (Fig. 2).

Mounted for rotation with the hollow shafts 38 and for axial movementrelative thereto, the heads 20 are urged upwardly to their normalposition as indicated in Fig. 5 by helical springs 54, one end of eachof which is seated on a shoulder 56 on the hollow shaft 30 and the otherend of which engages the head 2%). A rod 58 slidably mounted in each ofthe hollow shafts 30 and secured at one end by a machine screw 62 to thehead 29, and having a head or shoulder 64 at its other end engageablewith the end of the shaft 3i; serves to limit the upward movement of theheads 29. A cylindrical skirt 66 on each of the heads encircles aportion of bosses 61-61 formed on the housing 36.

'Ihe die extracting machine is provided with control means forcontrolling the rotation of the heads'in response to the placing of anarticle in into operative position on the machine. In the embodimentshown herein, the control means comprises a switch 10 secured totheupper portion of the housing 36 and to one side of the heads 20 and hasa spring biased plunger 12 stressed for movement upwardly to its normalopen position shown in Fig. 2. A switch operating lever 14 pivotallyconnected to the switch 10 at 16 has its end portion 18 positioned inthe path of movement of an article ID whenthe article is moved intooperative position on the machine and is engaged and actuated by thearticle to its closed position to start the motor and rotate the heads20.

Thus when it is desired to remove the pair of thread forming dies 12from the article H], the articlelfl isplaced in operative position onthe machine with thepair of dies positioned in engagement with the heads20. This movement of the article I into engagement withthe machinedepressesthe'lever T4 and actuates'the switch from its openposition toits closed position to cause. theactu'ation of the motor 28 and therotation of the' heads2ll 'whichimpart rotation to the :dies 12tolunscrewthemirom the threaded portion'lfi of the article '10. Duringthe die removing operation the article H] is held stationary while thethread rings I2.thereon, and the heads 20 of the machine are movedaxially in a downward direction until the dies l2 have beenunscrewe'dlfrom the-threaded portion i=6 of the article whenithe articleII] is raised,. and switch '10 a'n'd'the heads '20. are restored totheirnormal position. Because of 'th'eangular disposition ofthe dies [2and'the' headsi2'i! duringthe die removing operation, an interlockingconnection is established. between the heads 20 andthe dies l2 whichholdsjthe article iniitsopera'tive position against the spring biasedlever "H3 v and-serves to keep the switch'.10,.closed. and the motorandthe heads .20 rotating .until'the .dies I2 .have..been unscrewed fromthethrea'ded portion.l6,. at which time the article 10. is free .to movethereby permitting the plunger 72 and lever .14 to'raise the article andrestore the switch Into-its open position to stop the operation of the.machine. The article I 0 and therpain'ofthrea'drings 1.2 may then beremoved individuallyfrom themachine.

It". is .essential thatboth of the die rings 12 become. unscrewed fromthe threaded ends t6 of the article-mat approximately the same instantto insurethatboth die rings are removed from the article I before thelever 14 is permitted to be raised and cause the actuation of the switch'10 tostoptheoperation of the machine. When the numberof-threads on oneof .the threaded ends lfiro'f the. article. l-llis greater than on theother end, as in' the embodiment illustrated herein, the.

ratio-.ofithe .gears. 38 is suchasto vary the rate of .rotationof-theheads 20 to accomplish the simultaneous removaluof the die rings fromthe article. 7

It isfto. bennderstood that the above-described arrangements aresimplyillustrative of the application of the principles of theinvention. Numerous other arrangements may be readily devised by thoseskilled in the art which will embody the principles of the .inventionand fall within the spirit andscope thereof.

What isclaimed is:

1. A die extracting machine comprising a pair of rotatable dieremovingelementshaving. means fonning-"interlocking engagement with apair of threaded die rings on an article, means mounting said elementsfor rotation about converging axes and for limited axial movement from anormal position toward the intersection of said axes, spring means foryieldably urging said. elements to their normal positions, drive meansincluding a motor for simultaneously rotating said elements, and switchmeans engageable with said article when said article is moved intooperative position in said machine to effect the actuation of saiddriving means to unscrew said threaded die rings from said article.

'2. A die extracting machine comprising a pair of rotatable die removingelements having means forming interlocking engagement with a pair ofannular thread forming dies on an article, means mounting said elementsfor rotation about converging axes and for limited axial movement frompredetermined normal positions toward the intersection of said axes,spring means stressing said elements for movement to their normalpositions, drive means including a motor for simultaneously rotatingsaid elements, switch means actuatable by an article moved intooperative position in said machine to effect the actuation of said drivemeans to unscrew said dies from said article, and resilient means forstressing said article for movement from said operativepositionformoving said article uponoompletion-of the unscrewing of said diestherefrom to stop said drive means.

3., A mechanism for removing a pair of thread forming dies from a moldedarticle wherein the dies are angularly disposed with respecttoeach otheron the article comprising a pair of rotatable heads having anormalposition and adapted to be engaged by the dies on the moldedarticle andhaving means forming an interlockingdriving connection with the dies,meanszmounting said heads for rotation about converging axes and forlimited axial movement, drivinglmeans including an electric motor forsimultaneously rotating said heads, resilient means'for yieldablyretaining said heads in said normal position and permitting axialmovement of said heads as the dies are unscrewed from said moldedarticle, and control means for effecting the actuation of said drivemeans including a switch actuated by the movement of the molded articleinto operative engagement with said heads.

4. A mechanism for unscrewing a pair of thread forming dies from amolded article wherein the dies are disposed on predetermined convergingaxes comprising a pair" of shafts, supporting means mounting said shaftsfor rotation about converging axes corresponding to saidpredeterminedconverging axes, driving means operatively connected to said shaftsfor-simultaneously rotating said shafts, heads mounted for rotation withand for limited axial movement on said shafts, said heads having anormal position adapted to engage-said thread forming dies on saidmolded article and having means forming an interlocking drivingconnection with said dies, said heads and said dies being movableaxially during the unscrewing of the dies from the molded article,resilient means for'normally retaining said heads in said normalposition and permitting axial movement of said heads, control means foreffecting the actuation of said driving means including a member movablefrom a normal first position to a'second position by the placing of amolded article into operative engagement with the heads, said articlebeing held against removal during the die unscrewing operation by theinterlocking connection between the heads, the dies and said moldedarticle, and resilient means for returning said member to said firstposition and moving said article thereon upon completion of theunscrewing of the dies from the article to stop the actuation of saiddriving means.

5. A mechanism for removing a pair of annular thread forming dies from amolded article wherein the dies are disposed about predeterminedconverging axes comprising a pair of shafts, supporting means mountingsaid shafts for rotation about converging axes corresponding to saidpredetermined converging axes, driving'means operatively connected tosaid shafts for simultaneously rotating said shafts, heads mounted forrotation with and for axial movement relative to said shafts, said headshaving a normal position adapted to receive said annular dies on saidmolded article, circular aligning shoulders on said head concentric withthe axis of rotation thereof telescopingly engageable with the annulardies for aligning the dies relative to the heads, means on said headsengageable with said annular dies to form an interlocking engagementtherewith for imparting rotation thereto, means limiting the axialmovement of said heads in one direction to said normal position, andspring means for yieldably retaining said heads in normal position andpermitting axial movement of said heads as the annular dies areunscrewed for said molded article.

6. A mechanism for removing a pair of annular notched thread formingdies from a molded article wherein the dies are disposed aboutpredetermined converging axes comprising a pair of hollow shafts,supporting means mounting said shafts for rotation about converging axescorresponding to said predetermined converging axes, a beveled gearfixed to one end Of each of said shafts, drive means including a beveledgear meshing with the bevel gears on said shafts for rotating saidshafts, die removing heads onthe opposite ends of said shafts, meansmounting said heads for rotation with and for limited axial movement onsaid shafts, conical members on said heads concentric with the axes ofrotation thereof engageable with the annular die for aligning the dierelative to the heads, a plurality of members on said heads engageablein the notches in said annular dies for establishing a drivingconnection between said heads and said annular dies, spring meansdisposed within said hollow shafts for moving the heads to a normalposition and permitting the heads to move axially during the unscrewingof the annular dies from the molded article, and stop members on saidheads extending axially within said hollow shafts and having shouldersthereon engageable with said shafts for limiting iii the movementaxially in one direction of said heads to said normal position.

7. A mechanism for removing a pair of thread forming dies from a moldedarticle, wherein the dies are angularly disposed with respect to eachother on the article, comprising a, pair of rotatable heads having anormal position adapted to be engaged by the dies on the molded articleand having means forming an interlocking driving connection with thedies, means mounting said heads for rotation about converging axes andfor limited axial movement, driving means for rotating said heads,resilient means for yieldably retaining said heads in said normalposition and permitting axial movement of said heads as the dies areunscrewed from said molded article, and control means for effecting theactuation of said drive means including an element actuated by themovement of the molded article into operative engagement with saidheads.

8. A mechanism for removing thread forming dies from a molded articlecomprising a plurality of rotatable heads having a normal position andadapted to be engaged by the dies on the molded article and having meansforming an interlocking driving connection with the dies, means mountingsaid heads for rotation and for limited axial movement, driving meansfor rotating said heads, resilient means for returning said heads tosaid normal position and permitting axial movement of said heads as thedies are unscrewed from said molded article, a movable element having anormal position and actuatable to a second position by the movement ofthe article into operative engagement with said heads, control meansincluding said element for effecting the actuation of said drive meansin response to the movement of said element to said second position, andresilient means for returning said element to said normal position uponcompletion of the unscrewing of the dies from the article to stop theactuation of said driving means.

JOHN KREBS, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date Re.'20,232 Talboys Jan. 5, 19371,667,718 Connell May 1, 1928 1,901,436 Coates Mar. 14, 1933 2,069,882Hall Feb. 9, 1937 2,106,365 'Iiano Jan. 25, 1938 2,444,602 Hardie July6, 1948 FOREIGN PATENTS Number Country Date 338,572 Italy Mar. 31, 1936

